Same-DayMAU Repair & Service
- Gas train & burner service
- Blower motor & VFD repair
- Evap pad replacement
- DX coil / refrigerant service
Commercial MAU Service
Repair · Replacement · Balancing · Gas Heat · Evap Cooling
Make-Up AirUnitsCommercial MAU Service
Commercial MAU repair, replacement, and balancing across the Inland Empire — tempered supply air sized to your exhaust system, by licensed commercial techs.
10 Years
Inland Empire
EPA 608
Universal Certified
Same-Day
Emergency Dispatch
Both Counties
Riverside & SB
Inland Empire Make-Up Air Units
Make-Up Air Is The Half No One Thinks About
Every commercial kitchen exhaust hood pulls air out of the building. That air has to come from somewhere — and if it isn't coming from a properly sized, tempered make-up air unit (MAU), it's coming from the back door, the front door, gas-appliance flues backdrafting, and any other opening the building has. The result: back door slams when the hood turns on, dining room feels drafty, hood fails to capture smoke, and gas appliances start drafting CO backwards. Tech On Call services commercial MAU systems across the Inland Empire — repair, replacement, balancing to exhaust, and complete new installs.
Most failing MAUs we see are old direct-fired gas systems with worn modulating valves, failed evap pads, or burned-out blower motors. We service the gas train, the burner controls, the evap pads, the supply blower, and the controls — and we re-balance the supply CFM against the actual exhaust CFM. If the original MAU was undersized (a common shortcut on cheaper restaurant builds), we'll quote a properly sized replacement instead of patching a system that was wrong from day one.
For new installs we coordinate Manual D supply ducting, roof curb fabrication, gas piping, electrical, and the Title 24 / Building & Safety permit cycle. California requires tempered make-up air on virtually every commercial kitchen install — direct-fired gas heat plus evaporative cooling is the most common IE spec; indirect-fired gas plus DX cooling for higher-end builds. See related: exhaust hoods, exhaust fans.
Licensed & Insured
Same-Day Service
Flat-Rate Pricing
Both IE Counties
Symptoms
How To Spot An MAU Problem
Diagnose · Repair · Restore
01
Back Door Slams On Hood Start
Classic negative-pressure symptom — MAU undersized or failed.
02
Hood Not Capturing Smoke
MAU not supplying enough air to balance hood exhaust.
03
Drafts In Dining Room
Customer-facing air pulled into kitchen — bad pressure balance.
04
MAU Won't Heat / Cool
Gas train, modulating valve, evap pad, or DX coil failure.
05
Failed Health Inspection
Capture velocity below code traceable back to MAU imbalance.
06
Evap Pads Dry Or Scaled
Evap section failing — supply air arrives at outdoor temp, kitchen overheats.
MAU Services
Full MAU Coverage
Same-DayHigh ROIBalancing To Exhaust
- Paired CFM testing
- Damper & VFD adjustment
- Capture-velocity verification
- Documentation for inspection
Turn-KeyMAU Replacement
- Sized to actual exhaust CFM
- Direct-fired gas + evap or DX
- Curb + duct + gas + electrical
- Permit + Building & Safety
MAU Brands
Every Major MAU Brand
CaptiveAire, Greenheck, Reznor, Modine, Mammoth, Phoenix Manufacturing — we service the full commercial lineup.
AprilaireHoneywellTrane CleanEffectsLennox PureAirCarrier InfinityiWaveREME HALOAirScrubberBroanPanasonicGreenheckCaptiveAireLoren CookReznorModineMammothPhoenix ManufacturingChampion CoolerMasterCoolAerocool
MAU Types
Every MAU Configuration
01
Direct-Fired Gas Heat
Most common IE spec — efficient, simple, lower install cost.
02
Indirect-Fired Gas Heat
Heat exchanger isolated from supply air — required in some food applications.
03
Evaporative Cooling
Standard for IE restaurants — cheap to operate in dry months.
04
DX (Refrigerated) Cooling
Higher-end installs where evap cooling can't keep up during humid months.
05
Restaurant Kitchens
Full-service restaurants, bars, breweries — every commercial kitchen footprint.
06
Industrial / Welding
Industrial spaces with welding, painting, or process exhaust.
Process
How A Real MAU Job Runs
- 01
Call & Schedule
A real dispatcher answers — no phone tree. Same-day or next-morning ETA confirmed, and we text the tech's name and photo before arrival.
- 02
Inspection & Test
Flat-rate diagnostic. Tech measures static pressure, airflow (CFM), filter restriction, hood capture, and IAQ baseline — then explains findings in plain English.
- 03
Written Scope & Quote
You see the work and the price before anything starts. Diagnostic fee credits toward the repair when you proceed.
- 04
Install Or Repair
Most repairs (boots, dampers, fans, motors, filters) are completed same-visit. Larger ductwork or hood jobs scheduled within 48–72 hours.
- 05
Verify & Document
We retest static, CFM, and IAQ deltas and document everything — parts used, before/after numbers, warranty terms.
Inland Empire MAU Service
Balanced To Exhaust · Title 24 Compliant
The Other Half Of Every Hood.
01
EPA 608 Certified
Universal-certified techs on every repair, install, and recovery — R-410A, R-32, R-454B handled correctly.
02
Same-Day Response
When the AC quits in the Inland Empire heat, you don't have hours. Same-day dispatch across both counties.
03
Flat Pricing
Diagnostic and repair quoted before any work begins. The number on-site is the number on the invoice.
04
Maintenance Plans
Spring tune-ups, filter swaps, and priority dispatch on annual plans built for desert summers.
View PlansRelated Services
Keep Exploring Tech On Call
Service Areas
Serving All of Riverside & San Bernardino County
Service Area
Riverside County
27
Cities
Don't see your city? Call (909) 239-6364 — we likely cover your area.
MAU FAQ
Make-Up Air Questions
01
What does a make-up air unit do?
Supplies tempered outside air to a commercial kitchen to replace what the exhaust hood is pulling out. Without it the kitchen runs in negative pressure.
02
How do I know if my MAU is undersized?
Back door slams, dining room drafty, hood not capturing, gas appliances backdrafting. We test paired CFM.
03
How much does a new MAU cost?
$8,500–$28,000+ depending on CFM, heating fuel, cooling type, ductwork, gas, and electrical.
04
Do MAUs need to be heated and cooled?
California Title 24 typically requires tempered make-up air. Most IE installs use direct-fired gas + evap; high-end installs use indirect gas + DX.
05
Can you balance my MAU to my existing hood?
Yes — paired CFM testing and damper / VFD adjustment without replacing equipment when the MAU is sized correctly.
06
Do you handle permits and inspections?
Yes — Title 24 + Building & Safety permit pulled on every install. Documentation provided.
07
Do you do commercial kitchen hood cleaning?
We service, repair, and replace commercial exhaust hoods, fans, and make-up air units, and we coordinate NFPA 96 hood-cleaning intervals with certified partners. See commercial exhaust hoods.
08
What cities do you serve for ductwork and ventilation?
Every city in Riverside and San Bernardino County — Riverside, San Bernardino, Fontana, Rancho Cucamonga, Ontario, Corona, Moreno Valley, Temecula, Murrieta, Redlands, Hesperia, Victorville, and the Coachella Valley. High Desert dust loads drive a lot of our duct-cleaning and filter calls; coastal-IE humidity drives IAQ work.
09
Do you warranty ductwork and ventilation work?
Every ductwork install carries a workmanship warranty. Equipment — IAQ purifiers, dehumidifiers, exhaust fans, hoods — is registered with the manufacturer and most ship a 5–10 year parts warranty when registered within 60 days. We handle the paperwork.
10
Do you offer financing on whole-home IAQ or new ductwork?
Yes — financing is available on qualifying ductwork replacement, IAQ packages, and whole-home dehumidifier installs. We walk through monthly payment options and any SCE/SoCalGas rebates before you commit.